Clutch



Patented Oct. 22, 1946 CLUTCH Frank L. Hetzel, Hermosa Beach, and Voley E. Carstedt, Los Angeles, Calif.

Application June 24, 1944, Serial No. 541,886

3 Claims. l

This invention relates to clutches and more particularly to a clutch of the centrifugal type.

The general object of the invention is to provide an improved centrifugal clutch, which is simple in construction, efcient in operation, easy to repair and inexpensive te manufacture.

A more particular object is to provide an improved centrifugal clutch with means, actuated by centrifugal force, for causing the clutch inembers to be interen'gaged, when one of the clutch members is rotated above a predetermined speed.

A further object is to provide a centrifugal clutch with means for causing the clutch members to be interengaged during rotation of one of said members up to a predetermined speed, and including means actuated by centrifugal force, for causing the clutch members to be interengaged when one of the clutch members is rotated above said predetermined speed.

Other objects and advantages will appear hereinafter as this specification progresses.

rlhe invention is illustrated in the annexed drawings, which form a part of this specification, and in which:

Fig. 1 is an inner side view of one of the clutch members, with the friction ring removed from said member, and the actuating spring contracted to its inoperative position.

Fig. 2 is a longitudinal section of the clutch taken on line 2 2 of Fig. 5, with the clutch members disengaged and the clutch in its inoperative position.

Fig. 3 is a view like Fig. 1, except that the actuating spring of the clutch is shown in its expanded and operative position.

Fig. 4 is a view like Fig. 2, except that the clutch members are shown engaged with the clutch in its operative position.

Fig. 5 is a side View of the clutch.

Fig. Gris a cross section taken on line 6-6 of Fig. 7, of one of the clutch members of a modification of our invention, with the friction ring removed from said member and with the main actuating spring contracted to its inoperative position and the auxiliary spring contracted into its operative position, which positions of said springs, are assumed when either clutch member is rotated below a predetermined speed and the clutch is in its starting drive position.

Fig. '7 is a longitudinal section of the modification of our clutch, as illustrated in Fig. 6, taken on line 'I-'I of Fig. 6.

Fig. 8 is a view like Fig. 7 of the modification of our clutch show'n in Fig. 6, with the auxiliary spring expanded by centrifugal force out of en- 2 gag'ement with the `friction ring and the actuating spring expe'inded into engagement with said ring, which positions of said springs are assumed when said clutch member is rotated' above a predetermined speed and the clutch is in its power drive position.

Fig. 9 is 'a view like Fig. T of ,the modification of our clutch shown in Fig. 6; with the actuating spring contracted out of engagement with the friction ring and the auxiliaryspring expanded out of engagement 'with' said ring, when one o f the clutch members is rotated vby the power shaft at a predetermined speed, and the clutch as idling with its other member stationary and said power shaft turning ltherein. u v I l A Fig. 10 is a Afragamentary section taken on line 2'-2 of Fig; illiistrating` novel means for preventing ovne of the clutch members from sliding ma Shaft.`

Referring more particularly to the drawings in which corresponding parts are designated by the saine reference characters in all of the views our clutch includes primarily apair of clutch members I and 2, va fiat clutchvring 3 and an actuating coil spring 4 arranged in ring formation.

The clutch member I A is of circular dish formation, open at its forward side and Vformed with a hub 5, 'a side wall 6; a cylindrical peripheral wall I extending rforwardly from said side wall, and enlarged hub portion formed also integral with said side wall 6 andV extending forwardly therefrom tona'point within the forward annular edge of said cylindrical peripheral wall 1. Aplurality of pins- 9, preferably three, are secured in the enlarged hub ,portion 8 equidistant apart Yand project forwardly therefrom, slidably thrgh a correspondingl number of apen-ings IU, respectively, in the clutch ring 3,

near the' inner edge of said ring, whereby saidring is detachably mounted in operative position in the forward side of the clutch member I. An annular' friction clutehshoe II of suitable material is secured t the forward side of the clutch e, for engaging clutch member 2 Vas will be hereinafter more 'f'ullyudescribed In the crner between the side` wall 6 and the Cylindrical peripheral wall I` is formed an annularcam I2 to be engaged by theactuating coil spring 4 in the and for thepurpos'e hereinafter dbdl The` 4' is DS-tned Within the Clutch ilnb I arund 'the' periphiy I3 of the enlarged hubp'ort'in'- 8' f saidclutch member between the side wall 6` f said clutch meinber and the clutch ring 3`, with' the' ends of said spring con'ne'cted together by interengaging 3 hooks I4 and I5 formed onthe ends, respectively, of said spring; the spring being of such length that with its ends connected together it is contracted around and against the periphery I3 of the enlarged hub portion 8 underrproper tension in its ineffective position when the clutch member l is at rest, as illustrated in Figs. 1 and2`, for the purpose hereinafter described.

The clutch member 2 comprises a disc I6 with a hub Il extendingv outwardly therefrom in which hub is formed a grooved pulley I8 to receive a belt through which power may be transmitted by the clutch.

mitted by the clutch, through its pulley I8 and a belt extending around said pulley, to any suitable mechanism for driving said mechanism.

In the modification of our invention shown in Figs. 6 to 9 inclusive the construction is substantially the same as that shown in Figs. 1 to 5 inclusive, with the addition of an auxiliary coil spring 26 of smaller diameter kthan the diameter of the actuating springV 4, arrangedin ring formation of greater diameter thantheidiameter of the ring formation of said actuating spring 4 and surrounding said actuating spring, in its ring y formation, in the clutch member I, there being an The clutch member I is keyed on a drive shaft l I5 by a key 2.3 whileV ther clutch member 2 is turnably mounted on said shaftV and is maintained in its operative position on said shaft, with its disc I6 adjacent the forward end of the hub 5 and the forward edge of the CylindricalY peripheral wall l of the clutch member I, by a 4collar 2l secured on said shaft I9, by a set screw adjacent the forward fend of the hub I'I-of said clutch member 2, the shaftv I9 extending through and being operatively tted in the bores of the hubs 5 and I1 of the clutch members I and 2, respectively, with the key secured in the shaft IS and fitted in a groove 23 in the hub 5 of the clutch member I.

' The clutch member I is secured on the shaft lil against sliding on its key 20, by means of a set screw 24, threaded in the hub 5 of said clutch member and extending through said hub and through a longitudinal groove 25 in the bore of vsaid hub, into engagement with said shaft. The width of the groove 25 is greater than the diameter of the set screw 24, so that the end of said screw when tightened against the shaft I9 mayy upset the surface of said shaft around said screw end in said groove, which prevents sliding of the end of said screw on said shaft, and thus locks the clutch member I on said shaft against sliding on said shaft over the key 2D. Upon 4loosening said set screw 24 and withdrawing its endfrom the upset portion of the shaft I9 the clutch ymember I may be withdrawn from said shaft',l the key 2i) passing through the key groove 23 in the hub 5 of said clutch member and the upset portion of the shaft I9 passing through the groove 25.

The operation of the invention is as follows:

When the shaft I9 and the clutch member I, are at rest the actuating spring 4 is contracted by its tension around and into engagement with the periphery I3 of the enlarged hub portion 8 and into engagement with the side wall 6 of said clutch member, releasing the forward pressure of the spring against the clutch ring 3, whereby said clutch ring and its shoe II are allowed to move away from the disc I6 of the clutch member 2, releasing said shoe from said disc, said movement of said ring being permitted by the pins 9 sliding in the openings I!) in said ring, as illustrated in Figs. l and 2 of the drawings.

Rotation of the drive shaft I9 rotates the clutch member l, and, at a predetermined speed of rotation of said clutch member, the contracted actuating spring 4 is expanded outwardly by centrifugal force and is directed forwardly by its engagement with the cam I2, into engagement with the clutch ring 3, whereby said ring is moved forwardly, sliding on the pins 9 until thering shoe II, engages the disc I6 of the clutch member 2 with sufficient friction to cause the clutch member I to rotate the clutch member 2 so that the power of the shaft I!! may be transannular groove 2l in the inner side of the peripheral wall of said clutch member I at the outer end of the annular cam I2, into which rgroove said auxiliary spring 26 is expanded by centrifugal force when said clutch member I is rotated above a predetermined speed.

When the clutch member 2 is roated at any speed up to a predetermined speed, the auxiliary spring 26 is contracted, so that it engages the actuating spring 4 and the fiat clutch ring 3 (Figs. 6 and 7) and presses said ring and its shoe AI I outwardly until said shoe engages the disc IB of the clutch member 2 with suiiicient friction to cause the clutch mem-ber I and shaft I9 to be rotated slowly by the clutch member 2 at a speed below said predetermined speed. Above said predetermined speed said auxiliary spring 26 is expanded outwardly in its ring formation by centrifugal force, into the annular groove 21 in the peripheral wall 'l of the clutch member I, (Fig. 9) and the actuating spring 4 is expanded outwardly in its ring formation by centrifugal Aforce and is directed forwardly by its engagement with the cam l2 into engagement with the clutch ring 3 (Fig. 8) and said ring and its shoe II are thereby forced forwardly until said shoe engages the disc I6 of the clutch member 2 with sufficient friction to cause the clutch member I to rotate the clutch member 2, so that the power of the shaft i9 may be transmitted by the clutch through the pulley I8 on the clutch member 2 as aforesaid, above said predetermined speed.

We claim:

l. A. clutch as disclosed comprising a clutch member to be secured on a rotatable shaft, a second clutch member to be turnably mounted on said shaft, a clutch ring mounted to move laterally in said first clutch member, an actuating coil spring in said first clutch memberl arranged in ring formation and to be expanded by centrifugal force upon rotation of said first clutch member above a predetermined speed, and a cam in said first clutch member to be engaged by said spring when expanded to cause said spring to engage and move said clutch ring forwardly into frictional contact with said second clutch member to clutch said second clutch member to said first clutch member, an auxiliary spring in said rst clutch member arranged in ring formation surrounding said actuating spring in its ring formation and constructed and arranged to be contracted between said actuating spring and said clutch ring to force said clutch ring into frictional contact with said` second clutch member to clutch said clutch members together, -when said second clutch member is rotated below said predetermined speed, and said auxiliary spring being constructed and arranged to be expanded by centrifugal force out 'of effective frictional Contact with said clutch `ring when either of `said clutch members is rotated'above said predetermined speed.

2. A clutch as claimed in claim 1 in which the first clutch member is formed with an annular groove into which the auxiliary spring is expanded When either clutch member is rotated above a predetermined speed.

3. A clutch as disclosed comprising a first clutch member to be secured on a rotatable shaft, a second clutch member turnably mounted on said shaft, means for clutching said clutch members together when either of said clutch members is rotated below a predetermined speed, and means for automatically clutching said clutch members together when either of said clutch members is rotated above a predetermined speed and said rst clutching means is disengaged and thereby rendered inelective.

FRANK L. I-IETZEL.

VOLNEY E. CARSTEDT. 

